Armed merchantmanAn armed merchantman is a merchant ship equipped with guns, usually for defensive purposes, either by design or after the fact. In the days of sail, piracy and privateers, many merchantmen would be routinely armed, especially those engaging in long distance and high value trade. In more modern times, auxiliary cruisers were used offensively as merchant raiders to disrupt trade chiefly during both World War I and World War II, particularly by Germany.
Fast attack craftA fast attack craft (FAC) is a small, fast, agile, offensive, often affordable warship armed with anti-ship missiles, gun or torpedoes. FACs are usually operated in close proximity to land as they lack both the seakeeping and all-round defensive capabilities to survive in blue water. The size of the vessel also limits the fuel, stores and water supplies. In size they are usually between 50–800 tonnes and can reach speeds of . A fast attack craft's main advantage over other warship types is its affordability.
Type 93 torpedoThe Type 93 was a -diameter torpedo of the Imperial Japanese Navy (IJN), launched from surface ships. It is commonly referred to as the Long Lance by most modern English-language naval historians, a nickname given to it after the war by Samuel Eliot Morison, the chief historian of the U.S. Navy, who spent much of the war in the Pacific Theater. In Japanese references, the term Sanso gyorai is also used, in reference to its propulsion system. It was the most advanced naval torpedo in the world at the time.
Type VII submarineType VII U-boats were the most common type of German World War II U-boat. 703 boats were built by the end of the war. The lone surviving example, , is on display at the Laboe Naval Memorial located in Laboe, Schleswig-Holstein, Germany. The Type VII was based on earlier German submarine designs going back to the World War I Type UB III and especially the cancelled Type UG. The type UG was designed through the Dutch dummy company NV Ingenieurskantoor voor Scheepsbouw Den Haag (I.v.
Line of battleThe line of battle is a tactic in naval warfare in which a fleet of ships forms a line end to end. The first example of its use as a tactic is disputed—it has been variously claimed for dates ranging from 1502 to 1652. Line-of-battle tactics were in widespread use by 1675. Compared with prior naval tactics, in which two opposing ships closed on one another for individual combat, the line of battle has the advantage that each ship in the line can fire its broadside without fear of hitting a friendly ship.
Type 91 torpedoThe Type 91 was an aerial torpedo of the Imperial Japanese Navy. It was in service from 1931 to 1945. It was used in naval battles in World War II and was specially developed for attacks on ships in shallow harbours. The Type 91 aerial torpedo had two unique characteristics. Firstly, it used wooden stabilizers attached to the tail fins which were shed upon water entry. Secondly, it engaged an angular acceleration control system to control rolling movements, which was very advanced for its time.
TorpexTorpex ("Torpedo explosive") is a secondary explosive, 50% more powerful than TNT by mass. Torpex comprises 42% RDX, 40% TNT and 18% powdered aluminium. It was used in the Second World War from late 1942, at which time some used the names Torpex and RDX interchangeably, much to the confusion of today's historical researchers. Torpex proved to be particularly useful in underwater munitions because the aluminium component had the effect of making the explosive pulse last longer, which increased the destructive power.
G7e torpedoThe G7e torpedo was the standard electric torpedo used by the German Kriegsmarine submarines in World War II. It came in 20 different versions, with the initial model G7e(TII) in service at the outbreak of the war. Due to several problems, leading to the German "Torpedokrise" which lasted until the end of 1941, the improved G7e(TIII) took over as the standard electric torpedo used by German U-boats for the rest of the war. G7e torpedoes measured in diameter and about in length.
Pump-jetA pump-jet, hydrojet, or water jet is a marine system that produces a jet of water for propulsion. The mechanical arrangement may be a ducted propeller (axial-flow pump), a centrifugal pump, or a mixed flow pump which is a combination of both centrifugal and axial designs. The design also incorporates an intake to provide water to the pump and a nozzle to direct the flow of water out of the pump. A pump-jet works by having an intake (usually at the bottom of the hull) that allows water to pass underneath the vessel into the engines.
Aerial torpedoAn aerial torpedo (also known as an airborne torpedo or air-dropped torpedo) is a torpedo launched from a torpedo bomber aircraft into the water, after which the weapon propels itself to the target. First used in World War I, air-dropped torpedoes were used extensively in World War II, and remain in limited use. Aerial torpedoes are generally smaller and lighter than submarine- and surface-launched torpedoes. The idea of dropping lightweight torpedoes from aircraft was conceived in the early 1910s by Bradley A.
